algparam.h

#ifndef CRYPTOPP_ALGPARAM_H
#define CRYPTOPP_ALGPARAM_H

#include "cryptlib.h"
#include "smartptr.h"
#include "secblock.h"

NAMESPACE_BEGIN(CryptoPP)

//! used to pass byte array input as part of a NameValuePairs object
/*! the deepCopy option is used when the NameValuePairs object can't
        keep a copy of the data available */
class ConstByteArrayParameter
{
public:
        ConstByteArrayParameter(const char *data = NULL, bool deepCopy = false)
        {
                Assign((const byte *)data, data ? strlen(data) : 0, deepCopy);
        }
        ConstByteArrayParameter(const byte *data, size_t size, bool deepCopy = false)
        {
                Assign(data, size, deepCopy);
        }
        template <class T> ConstByteArrayParameter(const T &string, bool deepCopy = false)
        {
        CRYPTOPP_COMPILE_ASSERT(sizeof(CPP_TYPENAME T::value_type) == 1);
                Assign((const byte *)string.data(), string.size(), deepCopy);
        }

        void Assign(const byte *data, size_t size, bool deepCopy)
        {
                if (deepCopy)
                        m_block.Assign(data, size);
                else
                {
                        m_data = data;
                        m_size = size;
                }
                m_deepCopy = deepCopy;
        }

        const byte *begin() const {return m_deepCopy ? m_block.begin() : m_data;}
        const byte *end() const {return m_deepCopy ? m_block.end() : m_data + m_size;}
        size_t size() const {return m_deepCopy ? m_block.size() : m_size;}

private:
        bool m_deepCopy;
        const byte *m_data;
        size_t m_size;
        SecByteBlock m_block;
};

class ByteArrayParameter
{
public:
        ByteArrayParameter(byte *data = NULL, unsigned int size = 0)
                : m_data(data), m_size(size) {}
        ByteArrayParameter(SecByteBlock &block)
                : m_data(block.begin()), m_size(block.size()) {}

        byte *begin() const {return m_data;}
        byte *end() const {return m_data + m_size;}
        size_t size() const {return m_size;}

private:
        byte *m_data;
        size_t m_size;
};

class CRYPTOPP_DLL CombinedNameValuePairs : public NameValuePairs
{
public:
        CombinedNameValuePairs(const NameValuePairs &pairs1, const NameValuePairs &pairs2)
                : m_pairs1(pairs1), m_pairs2(pairs2) {}

        bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const;

private:
        const NameValuePairs &m_pairs1, &m_pairs2;
};

template <class T, class BASE>
class GetValueHelperClass
{
public:
        GetValueHelperClass(const T *pObject, const char *name, const std::type_info &valueType, void *pValue, const NameValuePairs *searchFirst)
                : m_pObject(pObject), m_name(name), m_valueType(&valueType), m_pValue(pValue), m_found(false), m_getValueNames(false)
        {
                if (strcmp(m_name, "ValueNames") == 0)
                {
                        m_found = m_getValueNames = true;
                        NameValuePairs::ThrowIfTypeMismatch(m_name, typeid(std::string), *m_valueType);
                        if (searchFirst)
                                searchFirst->GetVoidValue(m_name, valueType, pValue);
                        if (typeid(T) != typeid(BASE))
                                pObject->BASE::GetVoidValue(m_name, valueType, pValue);
                        ((*reinterpret_cast<std::string *>(m_pValue) += "ThisPointer:") += typeid(T).name()) += ';';
                }

                if (!m_found && strncmp(m_name, "ThisPointer:", 12) == 0 && strcmp(m_name+12, typeid(T).name()) == 0)
                {
                        NameValuePairs::ThrowIfTypeMismatch(m_name, typeid(T *), *m_valueType);
                        *reinterpret_cast<const T **>(pValue) = pObject;
                        m_found = true;
                        return;
                }

                if (!m_found && searchFirst)
                        m_found = searchFirst->GetVoidValue(m_name, valueType, pValue);
                
                if (!m_found && typeid(T) != typeid(BASE))
                        m_found = pObject->BASE::GetVoidValue(m_name, valueType, pValue);
        }

        operator bool() const {return m_found;}

        template <class R>
        GetValueHelperClass<T,BASE> & operator()(const char *name, const R & (T::*pm)() const)
        {
                if (m_getValueNames)
                        (*reinterpret_cast<std::string *>(m_pValue) += name) += ";";
                if (!m_found && strcmp(name, m_name) == 0)
                {
                        NameValuePairs::ThrowIfTypeMismatch(name, typeid(R), *m_valueType);
                        *reinterpret_cast<R *>(m_pValue) = (m_pObject->*pm)();
                        m_found = true;
                }
                return *this;
        }

        GetValueHelperClass<T,BASE> &Assignable()
        {
                if (m_getValueNames)
                        ((*reinterpret_cast<std::string *>(m_pValue) += "ThisObject:") += typeid(T).name()) += ';';
                if (!m_found && strncmp(m_name, "ThisObject:", 11) == 0 && strcmp(m_name+11, typeid(T).name()) == 0)
                {
                        NameValuePairs::ThrowIfTypeMismatch(m_name, typeid(T), *m_valueType);
                        *reinterpret_cast<T *>(m_pValue) = *m_pObject;
                        m_found = true;
                }
                return *this;
        }

private:
        const T *m_pObject;
        const char *m_name;
        const std::type_info *m_valueType;
        void *m_pValue;
        bool m_found, m_getValueNames;
};

template <class BASE, class T>
GetValueHelperClass<T, BASE> GetValueHelper(const T *pObject, const char *name, const std::type_info &valueType, void *pValue, const NameValuePairs *searchFirst=NULL, BASE *dummy=NULL)
{
        return GetValueHelperClass<T, BASE>(pObject, name, valueType, pValue, searchFirst);
}

template <class T>
GetValueHelperClass<T, T> GetValueHelper(const T *pObject, const char *name, const std::type_info &valueType, void *pValue, const NameValuePairs *searchFirst=NULL)
{
        return GetValueHelperClass<T, T>(pObject, name, valueType, pValue, searchFirst);
}

// ********************************************************

template <class R>
R Hack_DefaultValueFromConstReferenceType(const R &)
{
        return R();
}

template <class R>
bool Hack_GetValueIntoConstReference(const NameValuePairs &source, const char *name, const R &value)
{
        return source.GetValue(name, const_cast<R &>(value));
}

template <class T, class BASE>
class AssignFromHelperClass
{
public:
        AssignFromHelperClass(T *pObject, const NameValuePairs &source)
                : m_pObject(pObject), m_source(source), m_done(false)
        {
                if (source.GetThisObject(*pObject))
                        m_done = true;
                else if (typeid(BASE) != typeid(T))
                        pObject->BASE::AssignFrom(source);
        }

        template <class R>
        AssignFromHelperClass & operator()(const char *name, void (T::*pm)(R))  // VC60 workaround: "const R &" here causes compiler error
        {
                if (!m_done)
                {
                        R value = Hack_DefaultValueFromConstReferenceType(reinterpret_cast<R>(*(int *)NULL));
                        if (!Hack_GetValueIntoConstReference(m_source, name, value))
                                throw InvalidArgument(std::string(typeid(T).name()) + ": Missing required parameter '" + name + "'");
                        (m_pObject->*pm)(value);
                }
                return *this;
        }

        template <class R, class S>
        AssignFromHelperClass & operator()(const char *name1, const char *name2, void (T::*pm)(R, S))   // VC60 workaround: "const R &" here causes compiler error
        {
                if (!m_done)
                {
                        R value1 = Hack_DefaultValueFromConstReferenceType(reinterpret_cast<R>(*(int *)NULL));
                        if (!Hack_GetValueIntoConstReference(m_source, name1, value1))
                                throw InvalidArgument(std::string(typeid(T).name()) + ": Missing required parameter '" + name1 + "'");
                        S value2 = Hack_DefaultValueFromConstReferenceType(reinterpret_cast<S>(*(int *)NULL));
                        if (!Hack_GetValueIntoConstReference(m_source, name2, value2))
                                throw InvalidArgument(std::string(typeid(T).name()) + ": Missing required parameter '" + name2 + "'");
                        (m_pObject->*pm)(value1, value2);
                }
                return *this;
        }

private:
        T *m_pObject;
        const NameValuePairs &m_source;
        bool m_done;
};

template <class BASE, class T>
AssignFromHelperClass<T, BASE> AssignFromHelper(T *pObject, const NameValuePairs &source, BASE *dummy=NULL)
{
        return AssignFromHelperClass<T, BASE>(pObject, source);
}

template <class T>
AssignFromHelperClass<T, T> AssignFromHelper(T *pObject, const NameValuePairs &source)
{
        return AssignFromHelperClass<T, T>(pObject, source);
}

// ********************************************************

// to allow the linker to discard Integer code if not needed.
typedef bool (CRYPTOPP_API * PAssignIntToInteger)(const std::type_info &valueType, void *pInteger, const void *pInt);
CRYPTOPP_DLL extern PAssignIntToInteger g_pAssignIntToInteger;

CRYPTOPP_DLL const std::type_info & CRYPTOPP_API IntegerTypeId();

class CRYPTOPP_DLL AlgorithmParametersBase : public NameValuePairs
{
public:
        class ParameterNotUsed : public Exception
        {
        public: 
                ParameterNotUsed(const char *name) : Exception(OTHER_ERROR, std::string("AlgorithmParametersBase: parameter \"") + name + "\" not used") {}
        };

        AlgorithmParametersBase(const char *name, bool throwIfNotUsed)
                : m_name(name), m_throwIfNotUsed(throwIfNotUsed), m_used(false) {}

        ~AlgorithmParametersBase()
        {
#ifdef CRYPTOPP_UNCAUGHT_EXCEPTION_AVAILABLE
                if (!std::uncaught_exception())
#else
                try
#endif
                {
                        if (m_throwIfNotUsed && !m_used)
                                throw ParameterNotUsed(m_name);
                }
#ifndef CRYPTOPP_UNCAUGHT_EXCEPTION_AVAILABLE
                catch(...)
                {
                }
#endif
        }

        bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const;

protected:
        virtual void AssignValue(const char *name, const std::type_info &valueType, void *pValue) const =0;
        virtual const NameValuePairs & GetParent() const =0;

        const char *m_name;
        bool m_throwIfNotUsed;
        mutable bool m_used;
};

template <class T>
class AlgorithmParametersBase2 : public AlgorithmParametersBase
{
public:
        AlgorithmParametersBase2(const char *name, const T &value, bool throwIfNotUsed) : AlgorithmParametersBase(name, throwIfNotUsed), m_value(value) {}

        void AssignValue(const char *name, const std::type_info &valueType, void *pValue) const
        {
                // special case for retrieving an Integer parameter when an int was passed in
                if (!(g_pAssignIntToInteger != NULL && typeid(T) == typeid(int) && g_pAssignIntToInteger(valueType, pValue, &m_value)))
                {
                        ThrowIfTypeMismatch(name, typeid(T), valueType);
                        *reinterpret_cast<T *>(pValue) = m_value;
                }
        }

protected:
        T m_value;
};

template <class PARENT, class T>
class AlgorithmParameters : public AlgorithmParametersBase2<T>
{
public:
        AlgorithmParameters(const PARENT &parent, const char *name, const T &value, bool throwIfNotUsed)
                : AlgorithmParametersBase2<T>(name, value, throwIfNotUsed), m_parent(parent)
        {}

        AlgorithmParameters(const AlgorithmParameters &copy)
                : AlgorithmParametersBase2<T>(copy), m_parent(copy.m_parent)
        {
                copy.m_used = true;
        }

        template <class R>
        AlgorithmParameters<AlgorithmParameters<PARENT,T>, R> operator()(const char *name, const R &value) const
        {
                return AlgorithmParameters<AlgorithmParameters<PARENT,T>, R>(*this, name, value, this->m_throwIfNotUsed);
        }

        template <class R>
        AlgorithmParameters<AlgorithmParameters<PARENT,T>, R> operator()(const char *name, const R &value, bool throwIfNotUsed) const
        {
                return AlgorithmParameters<AlgorithmParameters<PARENT,T>, R>(*this, name, value, throwIfNotUsed);
        }

private:
        const NameValuePairs & GetParent() const {return m_parent;}
        PARENT m_parent;
};

//! Create an object that implements NameValuePairs for passing parameters
/*! \param throwIfNotUsed if true, the object will throw an exception if the value is not accessed
        \note throwIfNotUsed is ignored if using a compiler that does not support std::uncaught_exception(),
        such as MSVC 7.0 and earlier.
        \note A NameValuePairs object containing an arbitrary number of name value pairs may be constructed by
        repeatedly using operator() on the object returned by MakeParameters, for example:
        const NameValuePairs &parameters = MakeParameters(name1, value1)(name2, value2)(name3, value3);
*/
template <class T>
AlgorithmParameters<NullNameValuePairs,T> MakeParameters(const char *name, const T &value, bool throwIfNotUsed = true)
{
        return AlgorithmParameters<NullNameValuePairs,T>(g_nullNameValuePairs, name, value, throwIfNotUsed);
}

#define CRYPTOPP_GET_FUNCTION_ENTRY(name)               (Name::name(), &ThisClass::Get##name)
#define CRYPTOPP_SET_FUNCTION_ENTRY(name)               (Name::name(), &ThisClass::Set##name)
#define CRYPTOPP_SET_FUNCTION_ENTRY2(name1, name2)      (Name::name1(), Name::name2(), &ThisClass::Set##name1##And##name2)

NAMESPACE_END

#endif

---